Wheeled carriers are very popular among students, travelers, business professionals and others, because they combine large carrying capacity with the convenience of rolling the carrier instead of carrying it. In some instances, the wheeled carriers can also be fitted with straps and used as backpacks, which adds an extra level of comfort to the users. Despite numerous advantages of wheeled carriers over the carry-on luggage, wheeled carriers generally limit user's ability to move freely and quickly. Having recognized this problem, the present invention provides a novel backpack system with a foldable skateboard, which allows the system's users to use the backpack as a personal transportation device. The disclosed system can therefore be easily converted between a rolled backpack to its backpack/skateboard configuration. This flexibility of configuration options provides a great convenience to the system's users.